<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<form action="/login/" method="post">
    <p>用户名：</p>
    <input type="text" name="user" placeholder="请输入用户名">
    <p>密码：</p>
    <input type="password" name="pwd" placeholder="请输入密码">
    <p>验证码：</p>
    <input type="text" name="check_code" placeholder="请输入验证码">
    <img src="/check_code/" onclick="changck(this)">
    <input type="submit" value="登录">
</form>
<script>
    function changck(t) {
        t.src = t.src + '?';
    }
</script>
</body>
</html>